I've had beers ferment out overnight before. That doesn't mean it's done, though! Even after the bulk of active fermentation is over, the yeast will continue to finish up more slowly. In addition, the yeast will go back and digest their own waste products (like diacetyl) when fermentable sugars are gone. So give it the full week as instructed before transferring. As was mentioned, some of us don't even transfer any more but that is a new topic!
One thing I'd like to mention is that an explosive fermentation like that sometimes gets a bit "hot". If you pitch the yeast too warm, for example, and keep the beer in a warm area, the temperature inside the fermenter can get out of control. It's sometimes up to 10 degrees above ambient temperature! So, in a 72 degree room, the beer can be over 80 degrees! If you have a stick-on thermometer on the outside of the fermenter, that's helpful to monitor the actual fermentation temperature. I have a feeling that your beer got a bit too hot, and that's why it was so explosive.